Express power load center

ABSTRACT

A power load center comprises a first terminal block adapted to receive multiple high voltage DC power feeder pairs under normal operating conditions and a protector block adapted to receive the multiple high voltage DC power pairs from the first terminal block and to aggregate them.

CROSS REFERENCE TO RELATED APPLICATIONS

The present invention is a continuation of U.S. patent application Ser.No. 11/196,974 entitled EXPRESS POWER LOAD CENTER, filed Aug. 4, 2005which is related to and claims the benefit of U.S. provisional patentapplication Ser. No. 60/598,861 entitled EXPRESS POWER LOAD CENTER,filed Aug. 4, 2004, both of which are assigned to the assignee of thepresent invention, the entire contents of each of which are incorporatedby reference as if produced in their entirety herein. The presentinvention is further related to and claims the benefit of U.S.provisional patent application Ser. No. 60/424,277, entitledTELECOMMUNICATIONS INTERFACE, filed on Nov. 6, 2002 and U.S.non-provisional patent application Ser. No. 10/631,096, entitledTELECOMMUNICATIONS INTERFACE, filed on Jul. 31, 2003, U.S. provisionalpatent application Ser. No. 60/592,353 entitled REHABILITATING A SERVINGAREA INTERFACE CABINET AND TERMINAL FIELD WITHOUT SERVICE INTERRUPTION,filed Jul. 29, 2004, U.S. non-provisional patent application docketnumber INFRATEL.0018, entitled REHABILITATING A SERVING AREA INTERFACECABINET AND TERMINAL FIELD FOR BROADBAND SERVICES WITHOUT SERVICEINTERRUPTION, filed Jul. 29, 2005, U.S. non-provisional patentapplication Ser. No. 11/005,274 entitled REMOTE POWER NODE, filed Dec.6, 2004, U.S. non-provisional patent application Ser. No. 11/021,883entitled EMBEDDED HEAT EXCHANGER, filed Dec. 23, 2004, U.S. provisionalpatent application Ser. No. 60/628,433 entitled TELECOMMUNICATIONSINTERFACE ENHANCEMENTS, filed Nov. 16, 2004, U.S. provisional patentapplication Ser. No. 60/662,074, entitled DSLAM ENCLOSURE, filed Mar.15, 2005, U.S. provisional patent application Ser. No. 60/662,073,entitled FTTC DSLAM OVERLAY, filed Mar. 15, 2005, and U.S. provisionalpatent application Ser. No. 60/662,072, entitled ENCLOSURE HOUSINGMULTIPLE DSLAMs, filed Mar. 15, 2005, assigned to the assignee of thepresent invention, the entire contents of each of which are incorporatedby reference as if produced in their entirety herein.

FIELD OF THE INVENTION

The present invention is related to power provisioning and, morespecifically, to an express power load center.

BACKGROUND OF THE INVENTION

Telephone companies are working on ways of extending broadband servicesto as many of their customers as possible. This means that they mustfind ways to reach substantially all their customers with digitalsubscriber lines (DSLs). In order to do so, they are installing more andmore electronics such as DSLAMs and broadband loop carriers (BLCS) inremote locations away from central offices (COs) and remote terminals(RTs). Naturally, this electronic and fiber equipment needs to bepowered. If local power is to be used, an AC service and an expensive ACto DC converter must be provided at the remote site, along withbatteries for power backup and the recharging circuitry to go along withthem. As an alternative to AC power, the concept of providing DC powerfrom the CO or other convenient point by using existing copper cablefeeder pairs has many advantages. However, connecting multiple cablepairs to each individual DLSAM or other device could prove to beunwieldy, costly and cumbersome. Termination of the pairs, electricalprotection, and DC to DC conversion would need to be provided for eachDSLAM, fan tray, fiber multiplexer, etc., sometimes at the board level.Clearly, a solution that overcomes these limitations is needed.

SUMMARY OF THE INVENTION

The present invention discloses an express power load center for use inpowering remote telecommunication nodes, such as nodes that have beenestablished as part of new installations (Greenfield), nodes that havebeen created by a retrofit or rehabilitation of an existing service areainterface cabinet (SAIC), nodes that are required due to the broadbandupgrades or replacements of existing Digital Loop Carriers or RemoteTerminals, nodes that provide power to environmentally sealedMini-DSLAMs in OSP (Outside Plant) cabinets, or nodes that powerwireless installations, such as cellular and WiMAX. Express power, whichis also called network power or Optical Network Unit (ONU) power, allowsa remote cabinet to be powered by sending power to the cabinet fromanother remote cabinet or from the CO. Such power can be transported tothe remote site over twisted pair copper (either in the same cablesheath as voice and data or over a separate copper cable) or over copperconductors in composite cable (which includes fiber and copper in thesame sheath) or over coaxial power cables. In all instances, an expresspower cable is connected to the remote cabinet via pin pairs in theexpress power protection panel or through express terminal blocks.

Express power is typically used in a number of scenarios. For example,when AC power cannot be delivered to a remote site or cannot bedelivered economically, when greater reliability and control overcabinet powering is desired, when a centralized power distributionscheme is desired for fiber-to-the-curb, FTTC, or fiber-to-the-home,FTTH broad band deployments, when greater back-up power than can beprovided by local batteries is desired, or when local AC power issubject to frequent interruptions. Conventional line-powered systemsmust be designed for the peak load on the equipment. With the loadvarying over time (both short-term and long term) according to trafficdemand, such conventional designs must be designed for the peak load andare, therefore, inefficient. When a DSLAM is first installed, forexample, the load will be small. As more customers are connected, boththe average and peak loads will increase. When the first DSLAM shelf isexhausted, and a second is installed, there will be an increase in theelectrical load at the site. There are similar variations in the loadrepresented by fans, battery heaters, and other ancillary devices. Forexample, the fans will not operate as much at night or in the winter,and the battery heaters will not typically operate in the summer. Thepresent invention scales to match long term variances in the load.Further, batteries are used to “chop off the peaks” of the short termvariances and feeder pairs can be added as necessary as customers andtraffic grow at the site without using as many pairs as if the equipmentwas powered separately.

In one embodiment, a power load center comprises a first terminal blockadapted to receive multiple high voltage DC power feeder pairs, such as+/−190V DC, a protector block adapted to receive the multiple highvoltage DC power pairs from the first terminal block, a DC to DC voltageconverter adapted to receive aggregate high voltage feeder pairs andconvert them to the required electronic supply voltage, typically −48VDC, and a second terminal block to provide multiple −48V DC power taps.A second embodiment incorporates the above high voltage convertingmechanism, but also includes rechargeable batteries, battery heater, andthe necessary electronic circuitry to recharge the battery as well asmonitor the status of the load center.

In another embodiment, a power load center comprises a first terminalblock adapted to receive multiple high voltage DC power feeder pairs, aprotector block adapted to receive the multiple high voltage DC powerpairs from the first terminal block, a DC to DC voltage converteradapted to receive the multiple feeder pairs and convert them to −48VDC, and a power tap bus or second terminal block adapted to deliver the−48V DC power and to output it as multiple −48V DC power taps.

In a further embodiment, a method for powering a combined electronic andserving area interface cabinet comprises receiving at least one highvoltage power feeder pair, wherein the feeder pair is at least one of:+/−130V DC, around +/−130V DC, and above +/−130V DC, a protector blockadapted to receive the multiple high voltage DC power pairs from thefirst terminal block, aggregating the at least one high voltage powerfeeder pair with at least one other high voltage power feeder pair,receiving the aggregate feeder pairs, converting the aggregate feederpairs to at least one of: −48V DC, around −48V DC, and above −48V DC,receiving the converted power, and outputting the converted power asmultiple power taps, wherein the power taps are at least one of: −48VDC, around −48V DC, and above −48V DC.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts an express power load center block diagram utilized in acombined electronic and SAI cabinet, wherein batteries are providingpower for peak loads according to one embodiment of the presentinvention;

FIG. 2 depicts an express power load center block diagram whereinbatteries are utilized to provide power for the loads directly accordingto one embodiment of the present invention; and

FIG. 3 depicts an express power load center block diagram according toone embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIG. 1, an integrated electronic and serving areainterface (SAI) cabinet 10 is depicted. Such a cabinet is described inmore detail in one or more of the pending cross-referenced patentapplications. Generally, the integrated electronic and SAI cabinet 10includes an SAI side 12, and an electronic side which includes DSLAMs14, a battery compartment 16, and protection for DSLAM IN and OUT blocks18. An express power load center of the present invention is depicted asbeing located in a housing 20 of the cabinet 10. Although depicted assuch, the power load center may be housed in various other locations ofthe cabinet 10 and may be distributed throughout the cabinet 10.

The power load center of the present invention comprises a terminalblock 22 which is adapted to receive incoming pairs, such as +/−190V DCfeeder pairs, via a same cable, a separate cable, a composite cable, acoax cable, and the like. The terminal block 22 is coupled to aprotector block 24. The incoming pairs are fed into a DC-to-DCconverter. The +/−190V DC power is then converted via a DC to DCconverter 28 to −48V DC, sent via a −48V output bus 30 to a power tap 32(or second terminal block). Individual −48V DC power connections aremade to various components at a remote site such as DSLAMs 24, fans 36,heat exchangers and air conditioning 38, fiber optic equipment 40, andthe like.

Charger electronics 42 are coupled to the DC to DC converter 28 toprovide charging to maintain the floating voltage of the batteries. Thecharger electronics 42 are coupled to batteries 44 which are primarilyused to provide additional power during peak demand and for additionalusage requirements. A load sensor 48 is coupled to the output bus 30, topermit load sharing capabilities and to monitor the load.

In one embodiment, the present invention allows for the use of multiplehigh voltage power pairs, such as +/−190V DC power pairs to providepower to the SAIC node. The incoming pairs are terminated on a block andaggregated into a power bus. The +/−190V DC is then converted via a DCto DC converter to −48V DC or other such voltage as required by thefiber and electronic equipment, and the output is available on multiple−48V DC taps. Individual −48V DC power connections are made to variouselectronic and fiber components present at the remote site such as:DSLAMs. Broadband Loop Carrier (BLC) equipment, battery heaters, batteryrecharging circuitry, heat exchanger or air conditioning equipment,fiber optic equipment, wireless electronics, cooling fan(s), and thelike. Further, batteries are included to supplement power during peakloading of the electronic and fiber equipment. Although not arequirement, the power load center may be placed in a remotetelecommunication node that is established by a retrofit or arehabilitation of a serving area interface cabinet (also known as across-connect cabinet), or a retrofit or a rehabilitation of both aservice area interface cabinet and a remote terminal (or digital loopcarrier). Surge protection is also available for the high voltage powerfeeder pairs via a protector block, and rechargeable batteries can beused to supplement operating power during peak fiber and electronicequipment load periods.

The features of the present invention include:

1) An express power load center brings in multiple +/−190V DC powerfeeder pairs from the CO, a digital loop carrier remote terminal, aremote power node, or other remote location and terminates them at oneplace. It also outputs multiple −48V DC power taps at one place. Thisallows for load sharing thereby reducing the number of power pairs foreach site. As previously noted, DC power can be sent to the cabinet viaHDSL pairs, heavy gauge coax, and the like (which may be advantageous incases where telcos are placing a new fiber feeder to the site). Further,voltages of +/−130V DC and above can be used without departing from thescope of the present invention;

2) By bussing the input and output power to one DC to DC converter, theconverter function is not repeated at each DSLAM shelf, reducing boardcomponents and space;

3) Wiring is simplified, since input and output power connections can beaccommodated at one location;

4) Integral surge protection of the incoming feeder pairs can beprovided via the input bus prior to the converter without the need toprotect each feeder pair from surges and other transient voltages;

5) The unit could turn on indications when the load nears capacity. Thiscould signal the telco to hook up some more power feeder pairs. It wouldalso alarm the telco to the fact that one or more power input pairs mayhave failed; and

6) A potential problem with express power is that, as the cabinet getsfilled with equipment, the power load during peak periods can exceedwhat can be supplied from a reasonable number of +/−190V DC power pairs.In one embodiment of the present invention, a plurality of rechargeablebatteries (which are, for example, Lithium batteries because of theirsize and maintainability) are used to supplement the power inputs duringsuch peak periods. These batteries are not back-up batteries (which canbe utilized by the express power load center). The express power loadcenter trickle-charges the plurality of batteries during low usagetimes, and then brings them on line when the voltage on the −48V DC busfalls below a predetermined level.

Referring now to FIG. 2, another power load center of the presentinvention, which may be used in a number of cabinets, comprises aterminal block 22 (which is adapted to receive +/−190V DC feeder pairs)which is electrically coupled to a protector block 24. The incomingpairs (which, for example, currently exist and are received from anexisting facility) are aggregated into an input bus 26. The +/−190V DCis then converted via a DC to DC converter 28 to −48V DC, sent via a−48V output bus 54 to a power tap 32 (or second terminal block) via aload sensor 56 that permits load monitoring capabilities to monitor thesource of input power to individual −48V DC power connections made tovarious components at a remote site such as DSLAMs 24, fans 36, heatexchangers and air conditioning 38, fiber optic equipment 40, and thelike. A −48V DC power supply 50 is coupled to the DC to DC converter 28and to the batteries 52. In this scenario, the batteries 52 (and not theDC to DC converter 28) are providing all the load power.

The embodiments described above are only exemplary. Even though severalcharacteristics and advantages of the present invention have been setforth in the foregoing description together with details of the methodof the invention, the disclosure is illustrative only and changes may bemade within the principles of the invention to the full extent indicatedby the broad general meaning of the terms used in the attached claims.

Referring now to FIG. 3, another embodiment is presented whereby thehigh voltage input feeds 57 the DC to DC converter and battery charger58 and the DC output of the converter such as 48V DC, 60V DC and thelike is electronically monitored by a load sensor 59 for the purpose ofmonitoring and sending alarm and status information in the event of lowor missing input feed power, low output power, low battery voltage, andwhether output DC power is being provided by the batteries 44 or 52 orthe DC to DC converter. Referring to the embodiment above, such alarmsmay be remotely sent by the equipment being powered or directly from theexpress power load center.

In another embodiment, the high voltage input feeds 57 the DC to DCconverter and battery charger 58 and the DC output of the converter suchas 48 VDC, 60 VDC and the like is split between the output power bussand a trickle charging circuit connected to the batteries in order tomaintain the batteries at a fully charged state. The batteries arearranged so as to discharge into the output power buss, as required,during periods of peak power usage so as to maintain the output powerbuss at its nominal voltage level.

Although an exemplary embodiment of the present invention has beenillustrated in the accompanied drawings and described in the foregoingdetailed description, for example in relation to FIG. 3, it will beunderstood that the invention is not limited to the embodimentsdisclosed, but is capable of numerous rearrangements, modifications, andsubstitutions without departing from the spirit of the invention as setforth and defined by the following claims. For example, a greater numberof elements such as terminal blocks, protector blocks, converters, powersupplies, batteries, sensors, power taps and the like can be employedwith the present invention.

1. A power load center, comprising: a first terminal block adapted toreceive multiple high voltage DC power feeder pairs under normaloperating conditions; and a protector block adapted to receive themultiple high voltage DC power pairs from the first terminal block andto aggregate them.
 2. The power load center of claim 1, comprising a DCto DC voltage converter adapted to receive the aggregate feeder pairsand convert them to a required electronic supply voltage.
 3. The powerload center of claim 2 comprising a power tap bus adapted to receive theconverted aggregate feeder pairs and to output them as multiple powertaps.
 4. The power load center of claim 1, wherein the power feederpairs are at least one of: +/−190V DC; and around +/−130V DC to morethan +/−130V DC.
 5. The power load center of claim 1, wherein therequired electronic supply voltage is −48V DC.
 6. The power load centerof claim 1, wherein the multiple power taps are at least one of: −48VDC; 24V DC; and 60V DC.
 7. The power load center of claim 1, wherein−48V DC power connections are made to at least one of: DSLAMs; broadbandloop carrier equipment; battery heaters; battery recharging circuitry;heat exchanger or air conditioning equipment; fiber optic equipment;wireless equipment; and cooling fan(s).
 8. The power load center ofclaim 1 comprising multiple +/−190V DC power pairs to provide multiple−48V DC power taps.
 9. The power load center of claim 1 comprisingbatteries to supplement power during peak loading of electronic andfiber equipment.
 10. The power load center of claim 1, wherein theremote telecommunication node is established by a retrofit or arehabilitation of a serving area interface cabinet.
 11. The power loadcenter of claim 1, wherein the remote telecommunication node isestablished by a retrofit or a rehabilitation of both a service areainterface cabinet and a remote terminal.
 12. The power load center ofclaim 1 comprising surge protection for the high voltage power feederpairs.
 13. The power load center of claim 1 comprising rechargeablebatteries used to supplement operating power during peak fiber andelectronic equipment load periods.
 14. A power load center, comprising:a first terminal block adapted to receive multiple high voltage powerfeeder pairs under normal operating conditions; a protector blockadapted to receive the multiple high voltage DC power pairs from thefirst terminal block and to aggregate them; and a DC to DC voltageconverter adapted to receive the aggregate feeder pairs and convertthem; the DC to DC voltage converter electronically monitored by a loadsensor.
 15. The power load center of claim 15, wherein the load sensormonitors and sends alarm and status information based on at least oneof: low input feed power; missing input feed power; low output power;low battery voltage; and whether output DC power is being provided bybatteries; and whether output DC power is being provided by the DC to DCvoltage converter.
 16. The power load center of claim 15 comprising asecond terminal block adapted to receive the converted aggregate feederpairs and to output them as multiple power taps.
 17. The power loadcenter of claim 14, wherein the power feeder pairs are at least one of:received from an existing facility; and are existing feeder pairs. 18.The power load center of claim 14, wherein the DC to DC voltageconverter is not repeated at each shelf in the center, wherein the shelfis a DSLAM.
 19. The power load center of claim 14, wherein received andoutput power connections can be accommodated at one location.
 20. Amethod for powering a combined electronic and serving area interface(SAI) cabinet, comprising: receiving at least one high voltage powerfeeder pair; aggregating the at least one high voltage power feeder pairwith at least one other high voltage power feeder pair; receiving theaggregate feeder pairs; converting the aggregate feeder pairs;monitoring the converted aggregate feeder pairs; receiving the convertedand monitored power; and outputting the converted and monitored power asmultiple power taps.